Air circulator



May 29, 1951 QREAR 2,554,633

AIR CIRCULATOR Filed Aug. 21, 1945 2 Sheets-Sheet 1 Wmw w rzz'fi A J w w E HI PM I INVENTOR. ANDREW G @IPFAR BYQ/A 2 A. G. OREAR AIR CIRCULATOR May 29, 1951 2 Sheets-Sheet 2 Filed Aug. 21, 1945 .R A m m N. r & A WW2 M Y A B w fi fi Aw r a 6 Patented May 29, 1951 AIR CIRCULATOR Andrew G. Orear, Glendale, Calif., assignor to Trade-Wind Motorfans, Inc.,

Los Angeles,

Calif., a corporation of California Application August 21, 1945, Serial No. 611,715

8 Claims. 1

This invention has to do with an air circulator and it is a general object of the present invention to'provide a simple, inexpensive and effective device for circulating air to and from a compartment or area, as for instance to and from a photographic dark room, or the like.

There are numerous situations where it is desired to introduce air at certain times and to withdraw or exhaust air at other times. An example of such a situation is a photographic dark room. My present-invention is in no way concerned with photographic dark rooms as such, or is it concerned with'like compartments or structures, but it is concerned, generally, with a device or unit of equipment that can be advantageously laboratories, it is now necessary to use filtered air under pressure to prevent contamination of cultures. The pressure in the room is established to prevent leakage of outside air into the room in 1 a manner to contaminate the air in the room. Some pathological laboratories, like photographic dark rooms or laboratories, require exclusion of light.

It is a general object of my present invention to provide a simple, inexpensive and easily in- 15.;f0r moving air and the direction in which the i used in connection with such compartments or 1 structures.

For the purpose of illustration and to facilitate an understanding of the present invention, I will refer to my invention as applied to a photographic dark room. However, I wish it specifically understood that I do. not limit or restrict the scope or range of the inventionibecause of such specific reference.

In the case of a photographic dark room it is, of course, necessary that the room or compartment be light-tight, which ordinarily means that,

when it is in use or is closed there is no free flow of air into or out or the'compartment. In'some cases, complicated constructions are provided to establish light traps that willpass air and then fans are provided at other points to circulate the air. Such arrangements or constructions are usually complicated and expensive and are not always adequate or satisfactory answers to the problem.

Conditions similar to those just described also prevail in compartments used as chemical laboratories where fumes are present, or in compartments where it is desired to exclude light or to prevent outside currents of air at given times.

In the case of a photographic dark room it is also highly important that the air be free of dust or foreign matter such as lint or other particles that float in the air and which are introduced by means of an ordinary fan arrangement. Such foreign matter deposited in photographic solutions and on damp films or on photographic papers causes imperfections in the products produced. In the case of a photographic dark. room it is also important, particularly when certain processes are being carried out, that temperature conditions be maintained within reasonably narrow limits.

Further, in the case of some pathological stalled apparatus operable to introduce air into a dark room, or the like, and operable to Withdraw air from such a room. The device that I have provided involves, generally, a fan or blower air is moved is under control so that it can be moved either into or out of a room in connection with which the device is installed.

Another general object of the invention i to 5provide a device of the general character hereinabove referred to which forms a complete, effective light trap or, in other words, serves to check or prevent the passage of light either into or out of the room.

Another object of my invention is to provide an apparatus of the general character referred to including a filter or air cleaning unit which serves to remove dust, lint, or other foreign matter from air introduced into the room.

A further object of my invention is to provide an apparatus of the character last mentioned, that is, one involving an air filter which is such that the filter is removed or freed from the path of the air when the device is positioned to circulate air in the opposite direction or out of the room. Through the structure that I have provided free unobstructed flow or" air is gained when air is being circulated out of the room and the filter is removed from the air stream under this condition so that it is not needlessly clogged with trapped or entrained matter.

Another object of my invention is to provide an apparatus of the general character referred to involving or including an air heater in the stream of air handled by the device so that the air in the dark room can be maintained at a substantially uniform temperature.

The various objects and features of my invention will be fully understood from the following detailed description of typical preferred forms and applications of the invention, throughout which description reference made to the accompanying drawings, in which:

Fig. 1 is a sectional view of the apparatus that I have provided showing it in operating position in a wall and showing it set or positioned to circulate or deliver air into a room such as a dark room, or the like. Fig. 2 is a view similar to Fig. 1 showing the device set in the opposite position or in a manner to circulate air out of the room. Fig. 3 is a front view of the apparatus that I have provided, being a view taken substantially as indicated by line 3-3 on Fig. 1. Fig. 4 is a View taken substantially as indicated by line 4-4 on Fig. 1. Fig. 5 is a view similar to Fig. 1 showing another form in which the invention may be incorporated, and Fig. 6 is a view similar to Fig. 2 showing the form of the invention illustrated in Fig. 5.

The structure embodying the present invention involves, generally, a body A which is in the nature of a frame or housing, a fan or blower B preferably a motor driven blower unit, a shiftable control element C operable between two positions to effect control of the air movement in the manner desired, a filter or air cleaner D, an air heater E, and. various other elements and features of construction, all of which will appear from the following description.

The body A of the structure is preferably shaped and proportioned to be in the nature of a box-like unit applicable to a simple opening I!) formed in a wall W, or the like. In the preferred form of the invention the body includes, generally, a bottom II, a top I2, side walls I3 and inner and outer walls I4 and I5, respectively. The body A is provided primarily as the means or medium by which the structure is to be mounted in a wall, or the like, and to facilitate mounting of the body it is preferred to provide a flange I6 at one end to overlie the wall W. In practice the opening II] formed in the wall W may be made merely to approximately fit or receive the body A, in which case a light sealing Washer or gasket ll of felt, or the like, can be provided under the flange It as indicated in the drawings. When the body is in place in the wall opening III, as shown in Figs. 1 and 2 of the drawings the opening is completely closed against the passage of light.

A general function of the body A is to provide or form suitable air ducts or passages, and to form a support or carrier for the various other elements of the apparatus. In accordance with the broader principles of my invention the desired air passages or ducts can be established through the body between the inner and outer ends I4 and I5 in various manners.

In the two forms of the invention illustrated in the drawings I provide a very simple arrangement or construction involving essentially a main partition 29 in the body. The partition is preferably a flat plate or sheet of material completely dividing the interior of the box-like body into a blower chamber X and a duct chamber Y. In the preferred arrangement the partition 20 is horizontally disposed, as shown in the drawings, and is located intermediate the bottom II and the top I2 to extend across'the body between the sides I3 and from the inner end Id of the body to the outer end I5 thereof. I locate the partition 29 considerably closer to the bottom I I than the top I2 so that the blower chamber X is considerably larger than the duct chamber Y;

The blower chamber X accommodates the motor blower unit, as will be described, and the various parts of the body defining the chamber X are entirely free of openings except for the partition 2B which has openings that I will describe.

4 This is particularly true of the inner and outer ends I4 and I 5, which must be light tight so that no light can pass through the structure between the inner and outer ends, by way of the chamber X.

The outer end I5 of the body A has an opening 22 communicating with the duct chamber Y at the front or outer end of the structure, while the inner end I4 of the body has an opening 23 communicating with the duct chamber Y at the rear or inner end of the structure. The openings 22 and 23 are preferably made large, and in practice may be entirely unobstructed to provide free flow of air into and out of the duct chamber Y.

In accordance with my invention passage of both air and light through the duct chamber Y between the openings 22 and 23 is checked by a baiiie 25 located in the duct chamber Y intermediate its ends.

In the form of the invention shown in Figs. 1 to I, inclusive, the baiile 25 is a fixed bailie or is arranged in a fixed position in the body, and is located between a port 30 in the inner end portion of the partition 28 and a port 3! in the partition outward of the port 39. The ports 30 and 3| may vary in number, size and shape, as desired. In the case illustrated I have shown the ports as round openings in the partition 20 and I have shown two ports 36 which I will term inner ports and two ports 3! which I will term outer ports.

In practice the bafile construction provided in the duct chamber Y may vary widely. In the case illustrated. I have shown the baffle as extending continuously between the sides I3 of the body and as extending between the partition 20 and the bottom II of the body. The particular bafile illustrated is formed of sheet metal and has spaced oppositely curved walls 33 which extend downwardly from a U-shaped channel part 34 by which the bafile is connected with the partition 20 through a depending rib 35 on the partition. The engagement of the rib 35 in the channel 34 is such as to effectively prevent leakage of light at this point, and the spaced engagements of the outer ends of the side walls 33 of the bafiie with the bottom I I of the body effectively prevent leakage of light at the bottom of the body. If necessary, the parts just described can be permanently joined or sealed to positively assure against leakage of light.

The blower B provided in the structure is operable to circulate air through the ports 35 and 3| so that it is either drawn in through the ports SI and out through the ports 30, or in through the ports 30 and out through the ports 3i. The first mentioned direction of flow is indicated b the arrows in Fig. l, and the other direction of flow is indicated by the arrows in Fig. 2.

Since the blower B is primarily to circulate air it may, in accordance with the broader concepts of my invention, be any suitable form of fan or blower. I find it advantageous to employ a blower as distinguished from a fan and in the preferred construction I use a motor-blower unit wherein there is a single motor M driving two blowers 49, one at each end of the motor. The motor M is preferably a simple conventional electrical motor of the type used for this class of Work, and each blower 45 includes a case 4| with a central or axial air inlet opening 42 and an outer tangential air outlet 43. Y

A suitable rotor 44 operates in the case so that air entering the inlet opening 52 circulates around through the case and is discharged through the opening 43. In the form of the invention shown in-Figsgl to. 4, inclusive, the blower means'B is shiftable in the body being carried by the control means; C. In;this case the control means C is primarily in the nature of a control plate 555 which carries the motor blower unit above described, and has openings cooperating with the ports inthe partition 20.

The plate 59 fits against the partition 28, for instancait may be arranged to slide on the top of the partition 29 and the motor blower unit is mounted on the plate 50 so that the outlets 43 of the two blowers are toward the rear of the inner end of the structure and open downwardly, in register with openings 53 in the plate 55, which openings can be positioned in register with the ports 30, as shown in Fig.1, or in register with the ports 3| as shown in Fig. 2. Other openings 55 are provided in the plate 56 forward of the openings 53 and are in register with the openings 3| when the openings 53 are in register with the ports 30.

When the plate 59 is shifted to the forward position, as shown in Figs. 2, the openings 55 are out of register with the ports 3| while the inner end-56.. of the plate 59-. is forward, leaving the ports 30 uncovered or unobstructed, as clearly shown in Fig. ,2 of the drawings.

In an arrangement such as I have just described, where the motor blower unit shifts with the plate 50, it is necessary to provide a suit able electrical connection for supplying the motor, for instance, the motor may be supplied through fieXibl-e'wires or a flexible cablefil].

In accordance with my invention I provide means for operating the plate 50 between thetwo positions above described, that is, between the positions shown in Figs. 1 and 2. In a simple form of the invention this means may include an operating rod 58 attached to the inn-er end portion 56 of the plateto slidably pass through an opening 59 in the end M of the body A. The rod has a projecting or protruding part that can be conveniently engaged to facilitate operation. It is to be understood, of course, that a similar operating rod can be provided in the other end of the plate 50' to project from the front or forward end of the structure. However, ordinarily. it is only necessary or desirable to have a control at the inner end.

The filter or air cleaner D may be incorporated in the construction in various manners.

However, I prefer to combine it with the other elements so that it is in operating position only when the parts are positioned as shown in Fig. 1. The air filter is intended to clean the air handled by the apparatus to free it of dust. lint, or'other foreign matter, and in practice it may be a suitable body SI of the filtering material, such as glass wool or any maze type filler, or the like, retained by a screen 62 carried in a suitable case 63. Itis preferred, in practice, that the air filter be so constructed as to permit the filteringm'edium or cell to be easily removed and cleaned or renewed when this becomes necessary. In the preferred arrangement illustrated the case 63, which suitably carries the body or pack of filtering material,v is mounted on the top of the plate 50.

The heater E is provided for heating air cir culated by the apparatus and, in practice, may be located in any suitable part of the apparatus. In the particular arrangement shown in the drawings the heater includes a heating element or grid which maybe a typical resistance element found in electrical heaters and the heatitcloses the port St the-opening 53 registers Ill ing element is connected in a suitable energizing circuit by lines L supplied from a suitable source such as S. In the preferred application of the structure a thermostatic control 15 is provided in the line L between the source of energy S and the element 10 and in practice the thermostatic control 15 is located in the room or compartment serviced by the apparatus so that there is an automatic control of the heater acting to maintain a uniform temperature in the serviced room.

From the foregoing description it will be apparent that the structure that I have provided serves as an effective light trap preventing passage of light through the Wall W Where or in which the unit is installed, and at the same time the unit is operable to circulate air so that it is either introduced into or withdrawn from a room or compartment defined by the wall W. When the apparatus is set, as shown in Fig. l, and the blower B is put in operation through energization of the motor M, air flows in through the opening 22 in the outer end of the body A, passes through the duct portion of the case, and is deflected or directed upward by the baille25 to pass through the port 3! in the partition 20 through opening 55 in the plate 59 through the filter D and into the blower compartment X of the body. From the blower compartment X the air is free to enter the inlet openings 42 of the blowers from all directions and the blowers operate to deliver the air to the outlet openings 43 so that it passes through the openings 53 and ports 30 and is finally discharged through the opening 23' in the inner end of the body A.

It is to be understood that ordinary air will not be forced into a room without some provision having been made for escape so pressure does not build up.

If the heater E is in use the air thus circulated will be heated and if a suitable thermostatic control i5 is provided and is functioning the heat of the air will be suitably regulated.

If it is desired to exhaust air from the room, say for instance from a dark room or any room, to remove fumes, air borne dust or chemicals or to cool the room, or for any other reason, the control rod 58 is operated, shifting the plate to the position shown in Fig. 2 in which case a reverse flow of air is gained and this flow is totally free and unobstructed since the filter, which is not needed when air is being exhausted, is removed from'the path of the air as clearly shown in Fig. 2.

In the form of the invention illustrated in Figs. 5 and '6 the general construction may be substantially the same as that above dercribed, the principal difference being that the motor blower unit or, in other words, the blowers B, are set or are in fixed position in the body A and the bafiles it are. shifted to effect control of the apparatus. In this modified form of construction the partition 2i! in the body is substantially the same as that above described, in

, that it has ports 38 corresponding to the ports l and ports Bl corresponding to the ports 3|. Intermediate ports 38 are located between the ports 3% and Si However, in this case the control plate o instead' of sliding on top of the partition 28 slidably engages under the partition and carries the bafille 25.

The control plate 50 has an inner opening 53 and a second or outer opening 55% When the control plate 58 is positioned, as shown in Fig. 5,

with the port 30 and the opening 55 registers with the! port 3|. When the plate 55 is in the other position, as shown in Fig. 6, opening 53 registers with port 36 and opening 55 registers with port 39 while the plate covers port 3W. In this construction the filter D is arranged in conjunction with the partition 2% at or covering the port 3 l The shiitable control plate 56* has a depending rib 35 which carries the partition 25 which partition may be constructed in the general manner hereinabove described, except that in this case the lower ends of the sides 33 of the partition slide on the bottom ll of the case A. Except for the differences indicated the structure shown in Figs. 5 and 6 may be the same as that shown in Figs. 1 to l, inclusive.

Having described only typical preferred forms and applications of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variaticns or modifications that may appear to those skilled in the art and fall within the scope of the following claims:

Having described my invention, I claim:

1. In a device of the character described, a box like body having a partition therein dividing the interior of the body into a blower chamber and an elongate duct chamber, the: partition having two spaced openings therethrough connecting the chambers, the body having openings to the exterior thereof and at opposite end portions of the duct chamber, a baflie in the duct chamber intermediate its ends and between the openings in the partition and stopping direct flow of air from one end of the duct chamber to the other, a blower in and confined to the blower chamber and having an air inlet open to the blower chamber to receive air therefrom, and a shiftable control element slidably engaging the partition to shift relative thereto to selectively control the delivery of air from the blower to one or the other of the openings through the partition, the said element being related to the openings in the partition so that when air is delivered to one of the partition openings the other partition opening is free to pass air from the duct chamber to the blower chamber.

2. In apparatus of the character described, a box-shaped body having a fixed partition in it dividing its interior into two air handling cham" bers, one a blower chamber and the other an elongate duct chamber having openings to the exterior of the body at opposite end portions of said duct chamber, the partition having air handling ports therethrough spaced apart longitudinally of said duct chamber, the body being completely closed except for said openings at the end portions of the duct chamber; a bafiie in the duct chamber between the openings and between the said ports and completely dividing the duct chamber into two parts each in communication with one of said openings, a motor driven blower in the blower chamber and completely confined thereto and receiving air from the duct chamber, and a control plate in the body and shiftable therein longitudinally of the duct chamber and cooperatively engaged with the partition, the plate being shiftable to selectively control de livery of air from the blower to one or the other of the ports in the partition while the unselected port is free to pass air into the blower chamber.

3. A device of the character described including, a box-like body having a partition therein dividing the interior or" the body into a blower chamber and an elongate duct chamber, the

body having two spaced air openings to the exterior thereof at opposite end portions of the duct chamber, a blower confined within the blower chamber and having an air inlet constantly open to the interior of the body to receive air therefrom, an air filter in the body shiftable into and out of working position where it passes air received by the inlet of the blower, the partition having longitudinally spaced ports therethrough connecting the chambers, a baffle in the duct chamber between said ports and establishing spaced duct portions in the duct chamber one open to one of the body openings and the other open to the other body opening, and a shiitable control element slidably engaging the partition and carrying the blower, said element being shiftable in the body to selectively control the delivery of air from the blower to one or the other of the duct portions, the filter being carried by the control element to be operable thereby into and out of working position and being in said working position only when air from the blower is delivered to a particular one of the duct portions.

4. In apparatus of th character described, a closed box-shaped body having a fixed partition in it dividing it into a blower chamber and an elongate duct chamber having longitudinally spaced openings to the exterior of the body at the end portions of said duct chamber, the partition having two ports therethrough spaced apart longitudinally of the duct chamber, a battle in the duct chamber between the openings and between said ports and completely dividing the duct chamber into two portions each in communication with one of said openings, a blower in the blower chamber receiving air therefrom, a filter in the blower chamber having a working position registering with one of the ports and a retracted position clear of both of said ports, and a shiftable control plate with apertures therethrough and spaced longitudinally of the duct chamber, the blower being mounted on the plate with the outlet of the blower in communication with one of said apertures, the filter being mounted on the plate in register with the other of said apertures, the plate being engaged with and shiftable relative to the partition between two positions to selectively register the first mentioned aperture of the plate with one of the other of said ports of the partition, the filter being in working position when the plate is in one position and being in the retracted position when the plate is in the other position.

5. In apparatus of the character described, a box-shaped body having a partition fixed therein and dividing its interior into two air handling chambers, one a blower chamber and the other an elongate duct chamber having openings to the exterior of the body at opposite end portions of said duct chamber, the partition having ports therethrough spaced apart longitudinally of said duct chamber, the body being completely closed except for said openings at the end portions of the duct chamber, a bafile in th duct chamber between the openings and between the said ports and completely dividing the duct chamber into two parts each in communication with one of said openings, a motor driven blower in the blower chamber and completely confined thereto and receiving air from the duct chamber, and a control plate in the body and shiftable therein longitudinally of the duct chamber and cooperatively engaged with the partition, the plate being shiftable to selectively control delivery of air from the blower to one or the other of the ports in the partition while the unselected port is free to pass air to the blower chamber, the bafile in the duct chamber being fixed to the body to be stationary in the duct chamber.

6. In apparatus of the character described, a closed box-shaped body having a fixed substantially flat partition in it dividing it into a blower chamber and an elongate duct chamber having openings to the exterior of the body at the end portions of the duct chamber, the partition having two ports therethrough spaced apart longi tudinally of the duct chamber, a baffle in the duct chamber between the openings and between said ports and completely dividing the duct chamber into two portions each in communication with one of said openings, a motor driven blower in the blower chamber receiving air therefrom and completely confined thereto, a filter in the blower chamber having a working position registering with one of the ports and a retracted position clear of both of said ports, and a shiftable substantially fiat control plate with apertures therethrough spaced longitudinally of the duct chamber, the blower being mounted on the plate with the outlet of the blower in communication with one of said apertures' and the filter being mounted on the plate in register with the other of said apertures, the plate being engaged with and shiftable relative to the partition between two positions to selectively register the first mentioned aperture with one or the other of said ports of the partition, the filter being located on the plate to be in working position when the plate is in one position and to be in retracted position when the plate is in the other position, the baffie in the duct chamber being fixed to the body to be stationary in the duct chamber.

7. In apparatus of the character described, a box-shaped body having a fixed partition in it dividing its interior into two air handling chambers, one a blower chamber and the other an elongate duct chamber having openings to the exterior of the body at opposite end portions of said duct chamber, the partition" having ports therethrough spaced apart longitudinally of said duct chamber and the body being completely closed'except for said openings at the end portions of the duct chamber, a baffle in the duct chamber between the openings and between ports in the partition and completely dividing the duct chamber into two parts each in communication with one of said openings, a motor driven blower in the blower chamber and completely confined thereto and receiving air from the duct chamber, and a control plate in the body slidably engaged with the partition and shi'itable relative thereto longitudinally of the duct chamber, the plate being shiftable to selectively control delivery of air from the blower to one or another of the ports in the partition while an unselected port is free to pass air to the blower chamber, the bafiie in the duct chamber being fixed to the plate to be carried thereby and to shif therewith.

8. In apparatus of the character described, a closed box-shaped body having a substantially flat fixed partition in it dividing it into a blower chamber and an elongate duct chamber having longitudinally spaced openings to the exterior of the body at the end portions of said duct chamber, the partition having ports therethrough spaced apart longitudinally of the duct chamber, a baflie in the duct chamber between the openings and between adjacent ports and completely dividing the duct chamber into two portions each in communication with one of said openings, a motor driven blower in fixed position on the blower chamber and completely confined thereto and receiving air therefrom, a filter in fixed position in the blower chamber registering with a particular one of the ports, and a shiftable substantially flat control plate with apertures therethrough spaced longitudinally of the duct chamber, the plate being engaged with and shiftable relative to the partition between two positions to selectively register the first mentioned aperture with one or another of said ports of the partition and having a portion registering with and closing said particular port when the plate is in only one of said positions, the baflie in the duct chamber being fixed to the plateto be carried thereby and to shift therewith.

ANDREW G. OREAR.

REFERENCES CITED The following references are of record in the file of this patent:

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